Motorola 68HC08LD Electrical and Logical Differences, Analog/Digital Converter, Clock Settings

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Electrical and Logical Differences

In order to enable emulation, 1k Pull-up resistor is present on the Target Reset line.

The original ports A and B are used for the emulation and are rebuilt by the port replacement unit on the POD; therefore electrical characteristics are changed.

The IRQ line is also used to start the emulation mode of the CPU. During the execution of the user program a 220E resistor and an 100nF capacitor are present on the line, which causes RC delays on this pin.

The Analog/Digital Converter

The reference voltage for the ADC can be selected using jumpers J1 and J3 on the bottom board.

J2: VREFL reference voltage

The J2 jumper defines the VREFL source.

Position

VREFL connected to

1-2 (*)

GND

2-3

Target VREFL

Jumper J2 settings (* - factory default)

If the Target VREFL is selected, the VREFL from the target must be connected.

J5: VREFH reference voltage

The J5 jumper defines the VREFH source.

Position

VREFH connected to

1-2 (*)

CPU Power Supply

2-3

Target VREFH

Jumper J5 settings (* - factory default)

If the Target VREFH is selected, the VREFH from the target must be connected.

Clock Settings

Target clock source selection is done by jumpers J1 and J3. Both jumpers must be in the same position.

Position

Clock source

1-2 (*)

Target

2-3

Rebuilt on POD

Jumper J1 and J3 settings (* - factory default)

The Clock can be rebuilt on the POD with the R1, Q1, C8 and C9 clock circuit.

If internal clock is selected in the software, the jumper position is ignored.

 iSYSTEM, March 2004

6/12

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Contents Motorola 68HC08LD POD rev. B POD Hardware ReferenceIn-Circuit Emulation PODs Final Target Application Test Top board CPU Mask Information Emulated CPUClock Settings Electrical and Logical DifferencesAnalog/Digital Converter Position Vcc level Voltage settingsPorts Jumper Set RemovedGeneral HC08 Emulation Notes Internal RAM, Internal EepromSignal Connector Target AdaptersPOD Target Layout 34 36 38 40 42 44 46 33 35 37 39 41 43 45 iSYSTEM, March 11/12  iSYSTEM, March 12/12